Three-dimensional color lookup table mapping input RGB values across a grid to output RGB values for color grading and on-set monitoring.
A 3D LUT (Look-Up Table) is a color grading tool that assigns a defined output RGB value to every input RGB color value. Unlike a 1D LUT, which processes each color channel (red, green, blue) separately and independently, a 3D LUT maps a color cube where red, green, and blue each form an axis. This allows any color to be shifted relative to others – meaning it can affect multiple channels simultaneously.
This capability makes 3D LUTs suitable for complex, non-linear transformations that are not possible with simple 1D curves: such as selective color shifts, film stock emulations, or precisely preserving skin tones while re-coloring other image areas.
A 3D LUT does not store a specific output value for every possible color value. Instead, it establishes a lattice of control points within the color cube. If an input pixel value falls between these control points, the output value is interpolated – in most programs, this is done via trilinear interpolation from the eight corner points of the surrounding grid cell. The quality of this interpolation is crucial for avoiding artifacts.
The resolution of the lattice determines the precision: more control points per axis mean finer color transitions.
| Lattice Size | Total Control Points |
|---|---|
| 17 × 17 × 17 | 4,913 |
| 33 × 33 × 33 | 35,937 |
| 65 × 65 × 65 | 274,625 |
33 × 33 × 33 is considered a common standard. Typical bit depths range from 8, 10, and 12-bit up to 32-bit (floating-point). The .cube format has established itself as a cross-format industry standard, read by virtually all editing and grading software.
In practice, two types of application are distinguished:
On set, the DIT (Digital Imaging Technician) uses 3D LUTs for on-set monitoring to display the flat log image on the monitor in an evaluable or already look-similar representation. These same LUTs serve as a reference and starting point for later color correction in post-production.
I use 3D LUTs daily for on-set monitoring to give the director and myself a realistic preview of the final look. They're indispensable, especially with Log footage, because the raw image looks extremely flat and low contrast – the LUT immediately shows us how the scene will appear after color correction.
For me, 3D LUTs are a creative tool that helps me define and communicate the visual mood of my film right on set. I can test different looks and, together with the cinematographer and colorist, develop the perfect visual style that optimally supports my story.
3D LUTs save me time and money in post-production by creating an efficient workflow between shooting and color correction. Using standardized LUTs reduces the need for approval loops and correction passes, which significantly lowers costs in color grading and makes schedules more predictable.
1. Was beschreibt „3D-LUT" am besten?
2. Zu welchem Department gehört „3D-LUT"?
3. Wie viele verschiedene Fachperspektiven bietet dieser Eintrag?
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